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/**
******************************************************************************
* @file system_stm32f4xx.c
* @author MCD Application Team
* @version V1.1.0
* @date 10-April-2016
* @brief CMSIS Cortex-M4 Device Peripheral Access Layer System Source File.
* This file contains the system clock configuration for STM32F4xx devices,
* and is generated by the clock configuration tool
* stm32f4xx_Clock_Configuration_V1.1.0.xls
*
* 1. This file provides two functions and one global variable to be called from
* user application:
* - SystemInit(): Setups the system clock (System clock source, PLL Multiplier
* and Divider factors, AHB/APBx prescalers and Flash settings),
* depending on the configuration made in the clock xls tool.
* This function is called at startup just after reset and
* before branch to main program. This call is made inside
* the "startup_stm32f4xx.s" file.
*
* - SystemCoreClock variable: Contains the core clock (HCLK), it can be used
* by the user application to setup the SysTick
* timer or configure other parameters.
*
* - SystemCoreClockUpdate(): Updates the variable SystemCoreClock and must
* be called whenever the core clock is changed
* during program execution.
*
* 2. After each device reset the HSI (16 MHz) is used as system clock source.
* Then SystemInit() function is called, in "startup_stm32f4xx.s" file, to
* configure the system clock before to branch to main program.
*
* 3. If the system clock source selected by user fails to startup, the SystemInit()
* function will do nothing and HSI still used as system clock source. User can
* add some code to deal with this issue inside the SetSysClock() function.
*
* 4. The default value of HSE crystal is set to 25MHz, refer to "HSE_VALUE" define
* in "stm32f4xx.h" file. When HSE is used as system clock source, directly or
* through PLL, and you are using different crystal you have to adapt the HSE
* value to your own configuration.
*
* 5. This file configures the system clock as follows:
*=============================================================================
*=============================================================================
* Supported STM32F40xx/41xx/427x/437x devices
*-----------------------------------------------------------------------------
* System Clock source | HSI
*-----------------------------------------------------------------------------
* SYSCLK(Hz) | 16000000
*-----------------------------------------------------------------------------
* HCLK(Hz) | 16000000
*-----------------------------------------------------------------------------
* AHB Prescaler | 1
*-----------------------------------------------------------------------------
* APB1 Prescaler | 1
*-----------------------------------------------------------------------------
* APB2 Prescaler | 1
*-----------------------------------------------------------------------------
* HSE Frequency(Hz) | 8000000
*-----------------------------------------------------------------------------
* PLL_M | 9
*-----------------------------------------------------------------------------
* PLL_N | 192
*-----------------------------------------------------------------------------
* PLL_P | 6
*-----------------------------------------------------------------------------
* PLL_Q | 4
*-----------------------------------------------------------------------------
* PLLI2S_N | NA
*-----------------------------------------------------------------------------
* PLLI2S_R | NA
*-----------------------------------------------------------------------------
* I2S input clock | NA
*-----------------------------------------------------------------------------
* VDD(V) | 3.3
*-----------------------------------------------------------------------------
* Main regulator output voltage | Scale2 mode
*-----------------------------------------------------------------------------
* Flash Latency(WS) | 0
*-----------------------------------------------------------------------------
* Prefetch Buffer | OFF
*-----------------------------------------------------------------------------
* Instruction cache | ON
*-----------------------------------------------------------------------------
* Data cache | ON
*-----------------------------------------------------------------------------
* Require 48MHz for USB OTG FS, | Disabled
* SDIO and RNG clock |
*-----------------------------------------------------------------------------
*=============================================================================
******************************************************************************
* @attention
*
* <h2><center>&copy; COPYRIGHT 2013 STMicroelectronics</center></h2>
*
* Licensed under MCD-ST Liberty SW License Agreement V2, (the "License");
* You may not use this file except in compliance with the License.
* You may obtain a copy of the License at:
*
* http://www.st.com/software_license_agreement_liberty_v2
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
******************************************************************************
*/
/** @addtogroup CMSIS
* @{
*/
/** @addtogroup stm32f4xx_system
* @{
*/
/** @addtogroup STM32F4xx_System_Private_Includes
* @{
*/
#include "stm32f4xx.h"
/**
* @}
*/
/** @addtogroup STM32F4xx_System_Private_TypesDefinitions
* @{
*/
/**
* @}
*/
/** @addtogroup STM32F4xx_System_Private_Defines
* @{
*/
/************************* Miscellaneous Configuration ************************/
/*!< Uncomment the following line if you need to use external SRAM mounted
on STM324xG_EVAL/STM324x7I_EVAL board as data memory */
/* #define DATA_IN_ExtSRAM */
/*!< Uncomment the following line if you need to relocate your vector Table in
Internal SRAM. */
/* #define VECT_TAB_SRAM */
#define VECT_TAB_OFFSET 0x00 /*!< Vector Table base offset field.
This value must be a multiple of 0x200. */
/******************************************************************************/
/************************* PLL Parameters *************************************/
/* PLL_VCO = (HSE_VALUE or HSI_VALUE / PLL_M) * PLL_N */
#define PLL_M 9
#define PLL_N 192
/* SYSCLK = PLL_VCO / PLL_P */
#define PLL_P 6
/* USB OTG FS, SDIO and RNG Clock = PLL_VCO / PLLQ */
#define PLL_Q 4
/******************************************************************************/
/**
* @}
*/
/** @addtogroup STM32F4xx_System_Private_Macros
* @{
*/
/**
* @}
*/
/** @addtogroup STM32F4xx_System_Private_Variables
* @{
*/
uint32_t SystemCoreClock = 16000000;
__I uint8_t AHBPrescTable[16] = {0, 0, 0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 6, 7, 8, 9};
/**
* @}
*/
/** @addtogroup STM32F4xx_System_Private_FunctionPrototypes
* @{
*/
static void SetSysClock(void);
#ifdef DATA_IN_ExtSRAM
static void SystemInit_ExtMemCtl(void);
#endif /* DATA_IN_ExtSRAM */
/**
* @}
*/
/** @addtogroup STM32F4xx_System_Private_Functions
* @{
*/
/**
* @brief Setup the microcontroller system
* Initialize the Embedded Flash Interface, the PLL and update the
* SystemFrequency variable.
* @param None
* @retval None
*/
void SystemInit(void)
{
/* FPU settings ------------------------------------------------------------*/
#if (__FPU_PRESENT == 1) && (__FPU_USED == 1)
SCB->CPACR |= ((3UL << 10*2)|(3UL << 11*2)); /* set CP10 and CP11 Full Access */
#endif
/* Reset the RCC clock configuration to the default reset state ------------*/
/* Set HSION bit */
RCC->CR |= (uint32_t)0x00000001;
/* Reset CFGR register */
RCC->CFGR = 0x00000000;
/* Reset HSEON, CSSON and PLLON bits */
RCC->CR &= (uint32_t)0xFEF6FFFF;
/* Reset PLLCFGR register */
RCC->PLLCFGR = 0x24003010;
/* Reset HSEBYP bit */
RCC->CR &= (uint32_t)0xFFFBFFFF;
/* Disable all interrupts */
RCC->CIR = 0x00000000;
#ifdef DATA_IN_ExtSRAM
SystemInit_ExtMemCtl();
#endif /* DATA_IN_ExtSRAM */
/* Configure the System clock source, PLL Multiplier and Divider factors,
AHB/APBx prescalers and Flash settings ----------------------------------*/
SetSysClock();
/* Configure the Vector Table location add offset address ------------------*/
#ifdef VECT_TAB_SRAM
SCB->VTOR = SRAM_BASE | VECT_TAB_OFFSET; /* Vector Table Relocation in Internal SRAM */
#else
SCB->VTOR = FLASH_BASE | VECT_TAB_OFFSET; /* Vector Table Relocation in Internal FLASH */
#endif
}
/**
* @brief Update SystemCoreClock variable according to Clock Register Values.
* The SystemCoreClock variable contains the core clock (HCLK), it can
* be used by the user application to setup the SysTick timer or configure
* other parameters.
*
* @note Each time the core clock (HCLK) changes, this function must be called
* to update SystemCoreClock variable value. Otherwise, any configuration
* based on this variable will be incorrect.
*
* @note - The system frequency computed by this function is not the real
* frequency in the chip. It is calculated based on the predefined
* constant and the selected clock source:
*
* - If SYSCLK source is HSI, SystemCoreClock will contain the HSI_VALUE(*)
*
* - If SYSCLK source is HSE, SystemCoreClock will contain the HSE_VALUE(**)
*
* - If SYSCLK source is PLL, SystemCoreClock will contain the HSE_VALUE(**)
* or HSI_VALUE(*) multiplied/divided by the PLL factors.
*
* (*) HSI_VALUE is a constant defined in stm32f4xx.h file (default value
* 16 MHz) but the real value may vary depending on the variations
* in voltage and temperature.
*
* (**) HSE_VALUE is a constant defined in stm32f4xx.h file (default value
* 25 MHz), user has to ensure that HSE_VALUE is same as the real
* frequency of the crystal used. Otherwise, this function may
* have wrong result.
*
* - The result of this function could be not correct when using fractional
* value for HSE crystal.
*
* @param None
* @retval None
*/
void SystemCoreClockUpdate(void)
{
uint32_t tmp = 0, pllvco = 0, pllp = 2, pllsource = 0, pllm = 2;
/* Get SYSCLK source -------------------------------------------------------*/
tmp = RCC->CFGR & RCC_CFGR_SWS;
switch (tmp)
{
case 0x00: /* HSI used as system clock source */
SystemCoreClock = HSI_VALUE;
break;
case 0x04: /* HSE used as system clock source */
SystemCoreClock = HSE_VALUE;
break;
case 0x08: /* PLL used as system clock source */
/* PLL_VCO = (HSE_VALUE or HSI_VALUE / PLL_M) * PLL_N
SYSCLK = PLL_VCO / PLL_P
*/
pllsource = (RCC->PLLCFGR & RCC_PLLCFGR_PLLSRC) >> 22;
pllm = RCC->PLLCFGR & RCC_PLLCFGR_PLLM;
if (pllsource != 0)
{
/* HSE used as PLL clock source */
pllvco = (HSE_VALUE / pllm) * ((RCC->PLLCFGR & RCC_PLLCFGR_PLLN) >> 6);
}
else
{
/* HSI used as PLL clock source */
pllvco = (HSI_VALUE / pllm) * ((RCC->PLLCFGR & RCC_PLLCFGR_PLLN) >> 6);
}
pllp = (((RCC->PLLCFGR & RCC_PLLCFGR_PLLP) >>16) + 1 ) *2;
SystemCoreClock = pllvco/pllp;
break;
default:
SystemCoreClock = HSI_VALUE;
break;
}
/* Compute HCLK frequency --------------------------------------------------*/
/* Get HCLK prescaler */
tmp = AHBPrescTable[((RCC->CFGR & RCC_CFGR_HPRE) >> 4)];
/* HCLK frequency */
SystemCoreClock >>= tmp;
}
/**
* @brief Configures the System clock source, PLL Multiplier and Divider factors,
* AHB/APBx prescalers and Flash settings
* @Note This function should be called only once the RCC clock configuration
* is reset to the default reset state (done in SystemInit() function).
* @param None
* @retval None
*/
static void SetSysClock(void)
{
/******************************************************************************/
/* HSI used as System clock source */
/******************************************************************************/
/* At this stage the HSI is already enabled and used as System clock source */
/* Configure Flash prefetch, Instruction cache, Data cache and wait state */
FLASH->ACR = FLASH_ACR_ICEN |FLASH_ACR_DCEN |FLASH_ACR_LATENCY_0WS;
/* HCLK = SYSCLK / 1*/
RCC->CFGR |= RCC_CFGR_HPRE_DIV1;
/* PCLK2 = HCLK / 1*/
RCC->CFGR |= RCC_CFGR_PPRE2_DIV1;
/* PCLK1 = HCLK / 1*/
RCC->CFGR |= RCC_CFGR_PPRE1_DIV1;
}
/**
* @brief Setup the external memory controller. Called in startup_stm32f4xx.s
* before jump to __main
* @param None
* @retval None
*/
#ifdef DATA_IN_ExtSRAM
/**
* @brief Setup the external memory controller.
* Called in startup_stm32f4xx.s before jump to main.
* This function configures the external SRAM mounted on STM324xG_EVAL/STM324x7I_EVAL board
* This SRAM will be used as program data memory (including heap and stack).
* @param None
* @retval None
*/
void SystemInit_ExtMemCtl(void)
{
/*-- GPIOs Configuration -----------------------------------------------------*/
/*
+-------------------+--------------------+------------------+------------------+
+ SRAM pins assignment +
+-------------------+--------------------+------------------+------------------+
| PD0 <-> FSMC_D2 | PE0 <-> FSMC_NBL0 | PF0 <-> FSMC_A0 | PG0 <-> FSMC_A10 |
| PD1 <-> FSMC_D3 | PE1 <-> FSMC_NBL1 | PF1 <-> FSMC_A1 | PG1 <-> FSMC_A11 |
| PD4 <-> FSMC_NOE | PE2 <-> FSMC_A23 | PF2 <-> FSMC_A2 | PG2 <-> FSMC_A12 |
| PD5 <-> FSMC_NWE | PE3 <-> FSMC_A19 | PF3 <-> FSMC_A3 | PG3 <-> FSMC_A13 |
| PD8 <-> FSMC_D13 | PE4 <-> FSMC_A20 | PF4 <-> FSMC_A4 | PG4 <-> FSMC_A14 |
| PD9 <-> FSMC_D14 | PE5 <-> FSMC_A21 | PF5 <-> FSMC_A5 | PG5 <-> FSMC_A15 |
| PD10 <-> FSMC_D15 | PE6 <-> FSMC_A22 | PF12 <-> FSMC_A6 | PG9 <-> FSMC_NE2 |
| PD11 <-> FSMC_A16 | PE7 <-> FSMC_D4 | PF13 <-> FSMC_A7 |------------------+
| PD12 <-> FSMC_A17 | PE8 <-> FSMC_D5 | PF14 <-> FSMC_A8 |
| PD13 <-> FSMC_A18 | PE9 <-> FSMC_D6 | PF15 <-> FSMC_A9 |
| PD14 <-> FSMC_D0 | PE10 <-> FSMC_D7 |------------------+
| PD15 <-> FSMC_D1 | PE11 <-> FSMC_D8 |
+-------------------| PE12 <-> FSMC_D9 |
| PE13 <-> FSMC_D10 |
| PE14 <-> FSMC_D11 |
| PE15 <-> FSMC_D12 |
+--------------------+
*/
/* Enable GPIOD, GPIOE, GPIOF and GPIOG interface clock */
RCC->AHB1ENR |= 0x00000078;
/* Connect PDx pins to FSMC Alternate function */
GPIOD->AFR[0] = 0x00cc00cc;
GPIOD->AFR[1] = 0xcccccccc;
/* Configure PDx pins in Alternate function mode */
GPIOD->MODER = 0xaaaa0a0a;
/* Configure PDx pins speed to 100 MHz */
GPIOD->OSPEEDR = 0xffff0f0f;
/* Configure PDx pins Output type to push-pull */
GPIOD->OTYPER = 0x00000000;
/* No pull-up, pull-down for PDx pins */
GPIOD->PUPDR = 0x00000000;
/* Connect PEx pins to FSMC Alternate function */
GPIOE->AFR[0] = 0xcccccccc;
GPIOE->AFR[1] = 0xcccccccc;
/* Configure PEx pins in Alternate function mode */
GPIOE->MODER = 0xaaaaaaaa;
/* Configure PEx pins speed to 100 MHz */
GPIOE->OSPEEDR = 0xffffffff;
/* Configure PEx pins Output type to push-pull */
GPIOE->OTYPER = 0x00000000;
/* No pull-up, pull-down for PEx pins */
GPIOE->PUPDR = 0x00000000;
/* Connect PFx pins to FSMC Alternate function */
GPIOF->AFR[0] = 0x00cccccc;
GPIOF->AFR[1] = 0xcccc0000;
/* Configure PFx pins in Alternate function mode */
GPIOF->MODER = 0xaa000aaa;
/* Configure PFx pins speed to 100 MHz */
GPIOF->OSPEEDR = 0xff000fff;
/* Configure PFx pins Output type to push-pull */
GPIOF->OTYPER = 0x00000000;
/* No pull-up, pull-down for PFx pins */
GPIOF->PUPDR = 0x00000000;
/* Connect PGx pins to FSMC Alternate function */
GPIOG->AFR[0] = 0x00cccccc;
GPIOG->AFR[1] = 0x000000c0;
/* Configure PGx pins in Alternate function mode */
GPIOG->MODER = 0x00080aaa;
/* Configure PGx pins speed to 100 MHz */
GPIOG->OSPEEDR = 0x000c0fff;
/* Configure PGx pins Output type to push-pull */
GPIOG->OTYPER = 0x00000000;
/* No pull-up, pull-down for PGx pins */
GPIOG->PUPDR = 0x00000000;
/*-- FSMC Configuration ------------------------------------------------------*/
/* Enable the FSMC interface clock */
RCC->AHB3ENR |= 0x00000001;
/* Configure and enable Bank1_SRAM2 */
FSMC_Bank1->BTCR[2] = 0x00001011;
FSMC_Bank1->BTCR[3] = 0x00000201;
FSMC_Bank1E->BWTR[2] = 0x0fffffff;
/*
Bank1_SRAM2 is configured as follow:
p.FSMC_AddressSetupTime = 1;
p.FSMC_AddressHoldTime = 0;
p.FSMC_DataSetupTime = 2;
p.FSMC_BusTurnAroundDuration = 0;
p.FSMC_CLKDivision = 0;
p.FSMC_DataLatency = 0;
p.FSMC_AccessMode = FSMC_AccessMode_A;
FSMC_NORSRAMInitStructure.FSMC_Bank = FSMC_Bank1_NORSRAM2;
FSMC_NORSRAMInitStructure.FSMC_DataAddressMux = FSMC_DataAddressMux_Disable;
FSMC_NORSRAMInitStructure.FSMC_MemoryType = FSMC_MemoryType_SRAM;
FSMC_NORSRAMInitStructure.FSMC_MemoryDataWidth = FSMC_MemoryDataWidth_16b;
FSMC_NORSRAMInitStructure.FSMC_BurstAccessMode = FSMC_BurstAccessMode_Disable;
FSMC_NORSRAMInitStructure.FSMC_AsynchronousWait = FSMC_AsynchronousWait_Disable;
FSMC_NORSRAMInitStructure.FSMC_WaitSignalPolarity = FSMC_WaitSignalPolarity_Low;
FSMC_NORSRAMInitStructure.FSMC_WrapMode = FSMC_WrapMode_Disable;
FSMC_NORSRAMInitStructure.FSMC_WaitSignalActive = FSMC_WaitSignalActive_BeforeWaitState;
FSMC_NORSRAMInitStructure.FSMC_WriteOperation = FSMC_WriteOperation_Enable;
FSMC_NORSRAMInitStructure.FSMC_WaitSignal = FSMC_WaitSignal_Disable;
FSMC_NORSRAMInitStructure.FSMC_ExtendedMode = FSMC_ExtendedMode_Disable;
FSMC_NORSRAMInitStructure.FSMC_WriteBurst = FSMC_WriteBurst_Disable;
FSMC_NORSRAMInitStructure.FSMC_ReadWriteTimingStruct = &p;
FSMC_NORSRAMInitStructure.FSMC_WriteTimingStruct = &p;
*/
}
#endif /* DATA_IN_ExtSRAM */
/**
* @}
*/
/**
* @}
*/
/**
* @}
*/
/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/